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+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#ifndef __LED_H
+#define __LED_H
+
+#include <stdbool.h>
+#include <cyclic.h>
+#include <dm/ofnode.h>
+
+/**
+ * DOC: Overview
+ *
+ * Generic LED API provided when a supported compatible is defined in DeviceTree.
+ *
+ * To enable support for LEDs, enable the `CONFIG_LED` Kconfig option.
+ *
+ * The most common implementation is for GPIO-connected LEDs. If using GPIO-connected LEDs,
+ * enable the `LED_GPIO` Kconfig option.
+ *
+ * `LED_BLINK` support requires LED driver support and is therefore optional. If LED blink
+ * functionality is needed, enable the `LED_BLINK` Kconfig option. If LED driver doesn't
+ * support HW Blink, SW Blink can be used with the Cyclic framework by enabling the
+ * CONFIG_LED_SW_BLINK.
+ *
+ * Boot and Activity LEDs are also supported. These LEDs can signal various system operations
+ * during runtime, such as boot initialization, file transfers, and flash write/erase operations.
+ *
+ * To enable a Boot LED, enable `CONFIG_LED_BOOT` and define in `/options/u-boot` root node the
+ * property `boot-led`. This will enable the specified LED to blink and turn ON when
+ * the bootloader initializes correctly.
+ *
+ * To enable an Activity LED, enable `CONFIG_LED_ACTIVITY` and define in `/options/u-boot` root
+ * node the property `activity-led`.
+ * This will enable the specified LED to blink and turn ON during file transfers or flash
+ * write/erase operations.
+ *
+ * Both Boot and Activity LEDs provide a simple API to turn the LED ON or OFF:
+ * `led_boot_on()`, `led_boot_off()`, `led_activity_on()`, and `led_activity_off()`.
+ *
+ * Both configurations can optionally define a `boot/activity-led-period` property
+ * if `CONFIG_LED_BLINK` or `CONFIG_LED_SW_BLINK` is enabled for LED blink operations, which
+ * is usually used by the Activity LED. If not defined the default value of 250 (ms) is used.
+ *
+ * When `CONFIG_LED_BLINK` or `CONFIG_LED_SW_BLINK` is enabled, additional APIs are exposed:
+ * `led_boot_blink()` and `led_activity_blink()`. Note that if `CONFIG_LED_BLINK` or
+ * `CONFIG_LED_SW_BLINK` is disabled, these APIs will behave like the `led_boot_on()` and
+ * `led_activity_on()` APIs, respectively.
+ */
+
+struct udevice;
+
+/*
+ * value imported from linux:include/linux/uapi/linux/uleds.h
+ */
+#define LED_MAX_NAME_SIZE 64
+
+enum led_state_t {
+ LEDST_OFF = 0,
+ LEDST_ON = 1,
+ LEDST_TOGGLE,
+ LEDST_BLINK,
+
+ LEDST_COUNT,
+};
+
+enum led_sw_blink_state_t {
+ LED_SW_BLINK_ST_DISABLED,
+ LED_SW_BLINK_ST_NOT_READY,
+ LED_SW_BLINK_ST_OFF,
+ LED_SW_BLINK_ST_ON,
+};
+
+struct led_sw_blink {
+ enum led_sw_blink_state_t state;
+ struct udevice *dev;
+ struct cyclic_info cyclic;
+ const char cyclic_name[0];
+};
+
+/**
+ * struct led_uc_plat - Platform data the uclass stores about each device
+ *
+ * @label: LED label
+ * @default_state: LED default state
+ * @name: LED name, derived from function, color or function-enumerator
+ * property.
+ * @sw_blink: LED software blink struct
+ */
+struct led_uc_plat {
+ const char *label;
+ enum led_state_t default_state;
+ char name[LED_MAX_NAME_SIZE];
+#ifdef CONFIG_LED_SW_BLINK
+ struct led_sw_blink *sw_blink;
+#endif
+};
+
+/**
+ * struct led_uc_priv - Private data the uclass stores about each device
+ *
+ * @boot_led_label: Boot LED label
+ * @activity_led_label: Activity LED label
+ * @boot_led_dev: Boot LED dev
+ * @activity_led_dev: Activity LED dev
+ * @boot_led_period: Boot LED blink period
+ * @activity_led_period: Activity LED blink period
+ */
+struct led_uc_priv {
+#ifdef CONFIG_LED_BOOT
+ const char *boot_led_label;
+ int boot_led_period;
+#endif
+#ifdef CONFIG_LED_ACTIVITY
+ const char *activity_led_label;
+ int activity_led_period;
+#endif
+};
+
+struct led_ops {
+ /**
+ * set_state() - set the state of an LED
+ *
+ * @dev: LED device to change
+ * @state: LED state to set
+ * @return 0 if OK, -ve on error
+ */
+ int (*set_state)(struct udevice *dev, enum led_state_t state);
+
+ /**
+ * led_get_state() - get the state of an LED
+ *
+ * @dev: LED device to change
+ * @return LED state led_state_t, or -ve on error
+ */
+ enum led_state_t (*get_state)(struct udevice *dev);
+
+#ifdef CONFIG_LED_BLINK
+ /**
+ * led_set_period() - set the blink period of an LED
+ *
+ * Thie records the period if supported, or returns -ENOSYS if not.
+ * To start the LED blinking, use set_state().
+ *
+ * @dev: LED device to change
+ * @period_ms: LED blink period in milliseconds
+ * @return 0 if OK, -ve on error
+ */
+ int (*set_period)(struct udevice *dev, int period_ms);
+#endif
+};
+
+#define led_get_ops(dev) ((struct led_ops *)(dev)->driver->ops)
+
+/**
+ * led_get_by_label() - Find an LED device by label
+ *
+ * @label: LED label to look up
+ * @devp: Returns the associated device, if found
+ * Return: 0 if found, -ENODEV if not found, other -ve on error
+ */
+int led_get_by_label(const char *label, struct udevice **devp);
+
+/**
+ * led_set_state() - set the state of an LED
+ *
+ * @dev: LED device to change
+ * @state: LED state to set
+ * Return: 0 if OK, -ve on error
+ */
+int led_set_state(struct udevice *dev, enum led_state_t state);
+
+/**
+ * led_get_state() - get the state of an LED
+ *
+ * @dev: LED device to change
+ * Return: LED state led_state_t, or -ve on error
+ */
+enum led_state_t led_get_state(struct udevice *dev);
+
+/**
+ * led_set_period() - set the blink period of an LED
+ *
+ * @dev: LED device to change
+ * @period_ms: LED blink period in milliseconds
+ * Return: 0 if OK, -ve on error
+ */
+int led_set_period(struct udevice *dev, int period_ms);
+
+/**
+ * led_bind_generic() - bind children of parent to given driver
+ *
+ * @parent: Top-level LED device
+ * @driver_name: Driver for handling individual child nodes
+ */
+int led_bind_generic(struct udevice *parent, const char *driver_name);
+
+/* Internal functions for software blinking. Do not use them in your code */
+int led_sw_set_period(struct udevice *dev, int period_ms);
+bool led_sw_is_blinking(struct udevice *dev);
+bool led_sw_on_state_change(struct udevice *dev, enum led_state_t state);
+
+#ifdef CONFIG_LED_BOOT
+
+/**
+ * led_boot_on() - turn ON the designated LED for booting
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_boot_on(void);
+
+/**
+ * led_boot_off() - turn OFF the designated LED for booting
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_boot_off(void);
+
+#if defined(CONFIG_LED_BLINK) || defined(CONFIG_LED_SW_BLINK)
+/**
+ * led_boot_blink() - turn ON the designated LED for booting
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_boot_blink(void);
+
+#else
+/* If LED BLINK is not supported/enabled, fallback to LED ON */
+#define led_boot_blink led_boot_on
+#endif
+#else
+static inline int led_boot_on(void)
+{
+ return -ENOSYS;
+}
+
+static inline int led_boot_off(void)
+{
+ return -ENOSYS;
+}
+
+static inline int led_boot_blink(void)
+{
+ return -ENOSYS;
+}
+#endif
+
+#ifdef CONFIG_LED_ACTIVITY
+
+/**
+ * led_activity_on() - turn ON the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_on(void);
+
+/**
+ * led_activity_off() - turn OFF the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_off(void);
+
+#if defined(CONFIG_LED_BLINK) || defined(CONFIG_LED_SW_BLINK)
+/**
+ * led_activity_blink() - turn ON the designated LED for activity
+ *
+ * Return: 0 if OK, -ve on error
+ */
+int led_activity_blink(void);
+#else
+/* If LED BLINK is not supported/enabled, fallback to LED ON */
+#define led_activity_blink led_activity_on
+#endif
+#else
+static inline int led_activity_on(void)
+{
+ return -ENOSYS;
+}
+
+static inline int led_activity_off(void)
+{
+ return -ENOSYS;
+}
+
+static inline int led_activity_blink(void)
+{
+ return -ENOSYS;
+}
+#endif
+
+#endif